Squid External Authentication Question

I am implementing squid as an authenticated tunnel through our firewall.

I need to write a squid authentication module that goes against our own
authentication scheme. I understand how this is done -- I think. The
authentication program is passed the userid and password and comes back
with an OK or ERR.

The problem is this. Our authentication scheme not only verifies a
user's id and password, but also has information such as classification
(faculty, student) and school. We'd like to filter which web server a
user has access to based on their classification and school. The
problem is that my authentication module needs to see which URL the user
is going after. Can I access the URL, either in a file, or as a
wildcard in authenticate_options, or as an environment variable?

Thanks.

Wade

-- 
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Wade B. Komisar       Comp. Sys. Sr. Engineer, Advanced Technology Group
Komisar@Virginia.EDU  		        Office of Information Technology
voice: 804.924.7171                               University of Virginia
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